Application and development of fecal microbiota transplantation in the treatment of gastrointestinal and metabolic diseases: A review

Fecal microbiota transplantation (FMT) restores a balanced intestinal flora, which helps to cure recurrent Clostridium difficile infections (RCDI). FMT has also been used to treat other gastrointestinal diseases, including inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), and chronic constipation, as well as a variety of non-GI disorders. The purpose of this review is to discuss gut microbiota and FMT treatment of GI and non-GI diseases. An imbalanced gut microbiota is known to predispose one to Clostridium difficile infections (CDI), IBD, and IBS. However, the complex role of the gut microbiota in maintaining health is a newer concept that is being increasingly studied. The microbiome plays a major role in cellular immunity and metabolism and has been implicated in the pathogenesis of non-GI autoimmune diseases, chronic fatigue syndrome, obesity, and even some neuropsychiatric disorders. Many recent studies have reported that viral gastroenteritis can affect intestinal epithelial cells, and SARS-CoV-2 virus has been identified in the stool of infected patients. FMT is a highly effective cure for RCDI, but a better understanding of the gut microbiota in maintaining health and controlled studies of FMT in a variety of conditions are needed before FMT can be accepted and used clinically.